But first, let's back up one week to August 21, which was supposed to be the turning point for Germany's ruling Christian Democrats  - the day Angela Merkel threw her weight behind the beleaguered party leader Armin Laschet and turned around his flagging electoral fortunes. Instead, as the Financial Times notes, "it was a day of reckoning."

A poll that Saturday evening showed that support for the party had slumped to 22%, level with the left-of-centre Social Democrats. Data released earlier today from INSA, suggests the SPD had even pulled ahead significantly, rising to 25% while the CDU/CSU has collapsed to just 20%. This means that if its luck doesn't turn before polling day on September 26, the CDU could be heading for the worst election result in its history.